A group of fungal proteins shows distant similarity to the TIR domain and is also collected with significant E values in orf22/BAB83481 psi-blast searches. The conservation is not focused around the box1 and 2.

fasta of viridiplantae STIR proteins
-> graphical representation of the Pfam domains with a E value below 0.1 contained in those proteins (png)

-> This search reveals a weak similarity of the proximal region of chicken SEF (residues 310-450) to small bacterial proteins with a N-terminal TIR domain (BAB83481 and NP_662351). The similarities of the SEF/IL17R membrane proximal domain to these proteins is below conventionally used PSI-BLAST thresholds and are thus indicative of homology, but the significance has to be supported further. A reciprocal psi-blast allowed us to support the similarity of BAB83481 (aligns to 80.7% of the CD TIR domain) to SEFIR proteins and to collect the STIR family.

The STIR SUPERFAMILY protein set (fasta with too short sequences being excluded) was used to build a multiple sequence alignment (pdf).
A protein set made non-redundant with a cut off of 50% identity was used to construct a HMM. A subset including SEFIR proteins only was used to construct a SEFIR specific HMM.

Chicken SEF (cSEF) was isolated in a screen for FGF4/8 regulated genes in chicken facial mesenchyme. A summary on the initial experimental functional analysis of chicken SEF is published on the web.